any follow up on this ??? im in the same boat and dont want to take it all apart.
I have the code for the new radio, but people keep saying the VIN will not match on the HU >?? not sure about that lol.

If we have the unlock code, im not sure if the vin will lock out the unit.

As as side note, the plugs at the back of the navi and non navi ex head units (7" touch screen) are identical lol.